412 BENNETTITALES [CH. 



in size with Williamsonia flowers, another indication of the very 

 close agreement between the Williamsonia and Bennettites types 

 of strobili. Some flowers still in place show 16 bipinnate micro- 

 sporophylls that were petrified before the synangium-bearing 

 fronds unfolded^ The ramental scales and other tissues figured 

 by Schuster are of the usual type. A second specimen found as a 

 boulder in Silesia and named by Goeppert Raumeria Schulziana 

 may, as he suggests, be a younger example of C. Reichenbachiana. 

 Another Galician stem, probably also Lower Cretaceous in age, 

 is described by Raciborski^ as Cycadeoidea Niedzwiedzkii. 



Cycadeoidea gigantea Seward. 



This species is founded on a large stem from the Upper Purbeck 

 series of the Isle of Portland^ where it was discovered in a shaly 

 clay 17 ft above the great Dirt bed which yielded the trunks 

 described by Buckland and other authors (fig. 535). The stem 

 (fig. 554) is 1 met. 18 cm. high and has a maximum diameter of 

 1 met. 7 cm. It is the tallest fossil Cycadean stem so far found 

 in a single piece though Cycadeoidea Jenneyana probably reached 

 a greater height. The stem is eUiptical in section (fig. 537), a 

 form due in part at least to compression. The only tissues 

 preserved are in the superficial region of the peifeistent leaf- 

 bases. As the result of decay before minerahsation many of the 

 petiole-bases are represented by cavities or meshes in a prominent 

 reticulum of sihcified ramental scales. Towards the apex the 

 leaf-bases are smaller and a conical bud surrounded by Unear 

 scale-leaves occupies the summit: an irregular cap of ramental 

 scales forms the apex of the terminal bud. In section the bud 

 would no doubt present an appearance like that shown in Wieland's 

 photograph of the terminal cone of C. Marshiana^. There is 

 a striking resemblance both in the ramental cap and in the 

 form of the protective scales between the fossil stem and such a 

 Cycad as Encephalartos AUensteinii^ A remarkable feature of 

 C. gigantea is the absence of any fertile shoots among the leaf-bases. 

 In one tangential section a small bud was found, but it affords 



1 Wieland (08) p. 96. = Raciborski (92=). 



3 Seward (97) A. « Wieland (06) PI. xix. fig. 5. 



= Seward (97) A. figs. 3, 4, pp. 24, 32. 



